Resolved issue with Credit Memo posting Negative Encumbrance amounts

Users are able to post Encumbrance balances against open Purchase Orders. The line's encumbered PO balance will adjust based on posted invoices and credit memos. Once a PO line has been fully invoiced against, the encumbrance will have a $0 remaining encumbrance balance.

Fundamentals resolved an issue where posted credit memos were posting with a negative encumbrance amount, therefore resulting in an incorrect encumbrance balance. Credit Memos against a PO Invoice will now post as a positive amount, thereby increasing the net encumbered balance.